#include <iostream>
#include <string>
#include <cmath>
#include <unordered_map>

using namespace std;

bool is_prime(int n) {
  if (n <= 1) {
    return false;
  }
  for (int i = 2; i <= sqrt(n); ++i) {
    if (n % i == 0) {
      return false;
    }
  }
  return true;
}

int find_closest_prime(int n) {
  int step = 1;
  while (true) {
    if (is_prime(n + step)) {
      return n + step;
    }
    if (is_prime(n - step)) {
      return n - step;
    }
    step += 1;
  }
}

int main() {
  unordered_map<string, int> word_to_digit = {
    {"zero", 0},
    {"one", 1},
    {"two", 2},
    {"three", 3},
    {"four", 4},
    {"five", 5},
    {"six", 6},
    {"seven", 7},
    {"eight", 8},
    {"nine", 9}
  };

  string input_words;
  getline(cin, input_words); 

  string word;
  int number = 0;
  int count = 0;

  for (char c : input_words) {
    if (isspace(c)) { 
      try {
        number = number * 10 + word_to_digit.at(word);
        count++;
      } catch (const out_of_range& oor) {
        cout << "Wrong input" << endl;
        return 1;
      }
      word = "";
    } else {
      word += c;
    }
  }
  
  try {
    number = number * 10 + word_to_digit.at(word); 
    count++;
  } catch (const out_of_range& oor) {
    cout << "Wrong input" << endl;
    return 1;
  }

  if (count != 3 || number < 100 || number > 999) {
    cout << "Wrong input" << endl; 
  } else {
    cout << find_closest_prime(number) << endl;
  }

  return 0;
}
